Want a better night’s sleep? Crack open a window

It’s a matter that divides couples: Should we sleep with the window open or closed? Science has provided an answer to the question — and it’s a victory to Team Open.

A study published in the journalIndoor Air(yes, indoor air has its own journal) suggests opening your bedroom’s windows and doors reduces carbon dioxide levels, thereby improving sleep quality.

Researchers from Eindhoven University of Technology in the Netherlands recruited 17 single volunteers in their twenties and tracked their sleep over five nights, in both closed-up rooms and in rooms with an open window or door.

The participants’ sleep was rated via several methods: surveys that asked them to report on how rested they felt; armbands that tracked their movement, body temperature and sweat levels; and sensors under their pillows that measured how restless they were.

From these variables, the researchers could assess the participants’ sleep depth, their sleep latency (how long it took them to fall asleep once they settled in), and how many times they woke up during the night — which all improved in bedrooms that weren’t sealed tight.

“The findings of the current study implied that opening either a door or a window leads to better ventilation, as indicated by reduced [carbon dioxide] levels,” the researchers wrote.